I would think so, yea. UV (UV-B, to be precise, at 302nm) causes dimers between C's and T's. This, and also the fact that dimers will change the DNA's shape, might interfere with the sequencing reaction.

Sequencing results will probably not be affected, although the quality of the sequencing will likely be impacted. It's hard to imagine a way in which you would get a different sequence from UV exposure.

Sequencing results will probably not be affected, although the quality of the sequencing will likely be impacted. It's hard to imagine a way in which you would get a different sequence from UV exposure.

Perhaps a single polymerase at a single location, but remember that there are billions of such polymerases, all active at the same location at the same time. When a single or few of those fall off, nothing will happen to the sequence read.